Factors aFFecting serum albumin level in uremic patients receiving continuous ambulatory peritoneal dialysis

Objective: To examine the factors affecting serum albumin level in uremic patients receiving continuous ambulatory peritoneal dialysis (CAPD). Methods: One hundred and twenty-five patients with end-stage renal disease on CAPD in our center were recruited for this cross-sectional study. Patients receiving CAPD for less than 12 months (n = 36) or receiving concurrent intermittent hemodialysis (n = 6) were excluded. The remaining 83 patients were included in the analysis and stratified according to serum albumin level, as either normal (serum albumin ≥ 3.6 gm/dl) group or hypoalbuminemia (< 3.6 gm/dl) group. Latest data of nutrition parameter, dialysis adequacy and peritoneal transport function were collected from medical charts. Presence of peripheral edema, pulmonary edema or congestive heart failure (CHF) was considered as extracellular water (ECW) excess. Concurrent serum level of C-reactive protein (CRP) was recorded. Episodes of peritonitis, exit-site infection, systemic infection and hospitalization due to various causes within one year were also collected. Results: Demographic data showed that patients with hypoalbuminemia were associated with longer duration of dialysis and higher prevalence of diabetes mellitus (DM). Clinical characteristic analysis showed that serum albumin level just prior to initiation of CAPD, hematocrit, and total iron binding capacity (TIBC) were positively correlated with the current serum albumin level. Age, duration of dialysis, presence of diabetes mellitus, exit-site infection, systemic infection, ECW excess, cardiothoracic ratio, and all-cause hospitalization were negatively correlated with serum albumin level. Kt/V of urea, 4-hour dialysate-to-plasma (D/P) creatinine ratio, and serum CRP were not significantly correlated with serum albumin level. In multiple regression analysis, age, hematocrit, TIBC, systemic infection and ECW excess were independently associated with hypoalbuminemia. Conclusion: The causes of hypoalbuminemia in patients undergoing CAPD are multifactorial. Age, hematocrit, TIBC, systemic infection and ECW excess are independent factors that affect serum albumin level. (Acta Nephrologica 2008; 22: 173-179)